Five senior statistical and quantitative geneticists request Program Project support to enable them to work synergistically on the development and application of statistical methodology for the interpretation of large- scale genomic data and the characterization of the genetic architecture of complex traits. The program will be headed by Bruce Weir, Professor and Chair of Biostatistics at the University of Washington. His project is concerned with developing methodology for characterizing the associations among sets of alleles. Sharon Browning, Research Associate Professor of Biostatistics at the University of Washington, will work on methodology for the analysis of rare variant data. Greg Gibson, Professor of Biology at the Georgia Tech University, proposes an empirical investigation of rare variants with 96 gene expression traits in human peripheral blood from 2,100 individuals from four cohorts. Elizabeth Thompson, Professor of Statistics at the University of Washington, has an overall objective of the development of methods for the enhanced detection and resolution of genes contributing to complex quantitative genetic traits. Her approach will be through using dense SNP marker data for the detection and estimation of segments of gene identity by descent (ibd) shared among sets of individuals. Peter Visscher, Senior Principal Research Fellow at Queensland Institute, will develop and implement better methods to dissect trait variation and predict phenotypes from SNP and sequence data.